Electronic component insertion machines receive component carrying tapes and position the contained components on circuit boards. The carrier tape typically feeds into the insertion machine in a predetermined manner. The component carrier tape includes a storage tape having individual compartments proximate one lateral side for housing the electronic components and a cover tape extending over the openings of the individual compartments for maintaining the components within the tape. The carrier tape also includes advancement holes along the other lateral side for mating with the advancement mechanism of the feeding machine that unwinds the tape. In order for the component to be properly positioned on the circuit board, the component must be correctly oriented as it feeds into the insertion machine. Correctly positioning the tape on the reel is critical. If the tape is not fed in the proper orientation, the component can be installed in the circuit board in a reverse or wrong manner. Improper installation can result in the failure of the circuit board and possibly the failure of the machine in which the circuit board is installed.
Existing reels for winding tape include a hub about which the carrier tape is wound and an end plate positioned on either side of the hub. The end plates typically extend beyond the outer diameter of the hub to provide lateral support to the tape and prevent it from sliding off the reel. The reel hubs used with existing carrier tape winding machines include a tape receiving slot into which a first end of the carrier tape is inserted. These hubs include a "lead in" or opening at the point where the slot meets a peripheral surface of the hub. The carrier tape is wound over one of the edges of the lead in for frictionally retaining it within the slot. Typically, the tape receiving slots of existing reels include a constant rectangular cross section. An example of a reel having such a slot is shown in U.S. Pat. No. 4,747,553 to Ogawa. Slots having constant rectangular cross sections allow the tape to be inserted in any orientation and fed over either edge of the lead in as long as the machine engaging holes of the tape mate with the advancing mechanism of the feeding machine. The lack of a required tape orientation within the slot and a specific edge over which the tape must be reeled can result in the components being incorrectly oriented within the slot, the tape being reeled backwards on the hub and the carried components being incorrectly positioned on the circuit board. The frequency of these errors increases as the speed at which the reel operator has to work increases. If the carrier tape is not positioned on the reel so that the components are delivered to the insertion machine in their proper orientation or if the feeding portion of the tape can not engage the advancing mechanism, the customer will have to return the tape or be forced to re-reel it themselves. This can be very time consuming and aggravating. This is especially true with polar components. When polar components are improperly fed to the insertion machine and incorrectly installed on a circuit board, they can cause the circuit board and the device carrying the board to fail.
It is an object of the present invention to overcome the problems associated with existing reels for winding carrier tapes. It is also an object of the present invention to provide a reel having a tape receiving slot that prevents a component carrying tape from being improperly oriented on the reel and incorrectly wound about the reel hub.